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Updated: Feb 4, 2026

Chemoselective Modification of Viral Surfaces via Bioorthogonal Click Chemistry
Published on: August 19, 2012
Bioorthogonal Metalloporphyrin-Catalyzed Selective Methionine Alkylation in the Lanthipeptide Nisin
Ruben V Maaskant1, Gerard Roelfes1
1Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747AG, Groningen, The Netherlands.
Abstract:
Bioorthogonal catalytic modification of ribosomally synthesized and post-translationally modified peptides (RiPPs) is a promising approach to obtaining novel antimicrobial peptides with improved properties and/or activities. Here, we present the serendipitous discovery of a selective and rapid method for the alkylation of methionines in the lanthipeptide nisin. Using carbenes, formed from water-soluble metalloporphyrins and diazoacetates, methionines are alkylated to obtain sulfonium ions. The formed sulfonium ions are stable, but can be further reacted to obtain functionalized methionine analogues, expanding the toolbox of chemical posttranslational modification even further.
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